import os


def check_append_file(prompt: str) -> str:
    if "@" in prompt:
        parts = prompt.split(" ")
        content = []
        for part in parts:
            if part.startswith("@"):
                filename = part[1:]
                try:
                    if os.path.exists(filename):
                        with open(filename, "r") as f:
                            content.append("%s:'''\n%s'''" % (filename, f.read()))
                except FileNotFoundError:
                    print(f"File '{filename}' not found.")
        content.append(prompt)
        return "\n".join(content)
    return prompt



if __name__ == "__main__":
    exit()  # not accidentally trigger it

    # Create some sample files
    with open("fmain.py", "w") as f:
        f.write("# This is main.py\n")
    with open("finference.py", "w") as f:
        f.write("# This is inference.py\n")

    # Test cases
    test_prompts = [
        "@fmain.py",
        "@fmain.py @finference.py",
        "@fnonexistent.py",
        "@fmain.py @fnonexistent.py"
    ]

    for prompt in test_prompts:
        print(f"Testing prompt: {prompt}")
        result = check_append_file(prompt)
        print(f"Result: {result}")
        print("-" * 20)